Which will have more resistance: 220V, 100W bulb or a 220V, 60W bulb?

The power dissipated by something with voltage across it is

(voltage) ² / (resistance).

You can see that resistance is in the denominator of the fraction,

so larger resistances dissipate less power, and smaller resistances

dissipate more power.

Here's an easy way to remember it:

- - Connecting a piece of rubber (high resistance) across the terminals of a battery

uses very little power from the battery.

- - Laying a piece of wire (low resistance) across the terminals of a battery

may draw so much power from the battery that the wire melts.

Since the voltage across both bulbs is expected to be the same, the bulb

designed to dissipate 60 watts has higher resistance than the one designed

to dissipate 100 watts.